Hoppers whose name never meant "I don't know"
Kangaroos are the big macropods—red, antilopine, eastern grey, and western grey—native to Australia and New Guinea. Large males can stand about two metres and weigh ninety kilograms. Australia's government estimated 42.8 million in commercial harvest zones in 2019, down from 53.2 million in 2013. They are the only large mammals that hop as their main gait.
"Kangaroo," "wallaroo," and "wallaby" are size nicknames inside Macropodidae, not clean clades. Females carry joeys in a pouch; grazing teeth crop close, and molars migrate forward and shed as silica wears them—polyphyodonty otherwise seen in elephants and manatees. Red kangaroos dominate arid interiors; eastern greys are actually more numerous. Comfortable hops run about twenty to twenty-five kilometres per hour, with short bursts near seventy and sustained forty for nearly two kilometres; seventy percent of hop energy stores in elastic tendons.
The English word comes from Guugu Yimithirr gangurru for eastern greys, recorded by Joseph Banks on 12 July 1770 near modern Cooktown while Endeavour was repaired. A durable myth claimed locals said "I don't know"; Walter Roth challenged it by 1898, and John Haviland's 1972 fieldwork confirmed gangurru named a real dark large kangaroo. Tree-kangaroos climb New Guinea and far-north Queensland canopies; many small macropods are rare while the big grazers thrived on cleared pastoral land.
National symbols put kangaroos on the coat of arms, currency, Qantas, and RAAF roundels. Wild animals are harvested for meat, hides, and pasture protection; meat is marketed for low fat. Red kangaroos appear geologically young, with fossils only from the Pleistocene about one to two million years ago, after Miocene drying pushed macropods from forest canopies onto grasslands with foregut fermentation. That shift from trees to open plains still shapes how they move and feed today.
Source: Kangaroo
